I've messed with Asta a time or two.
Astaroth's most powerful tools are his ranged, hard hitting attacks and his throws. In order to get this match up in your favor. You need to be making him block you and attempt throwing Maxi around like a ragdoll. Granted, better Maxi's will be sniffing for ways to interrupt. Maxi likes to be mid to close. Any Maxi smart enough knows being close to Astaroth will result in unfriendly hugs. Thus, they may try to space WAY back and make you attempt whiff something so they can run up and smack the shit out of you.
I dunno what Astaroth players are doing but here are some tips from personal history...
1. GI: If Maxi is giving you a rough time, try and time a GI. Yes it uses meter, but it can be a DEADLY momentum stopper. Astaroth's post-GI throw/mid hit game is great here. REMEMBER! GI now covers ALL areas, Highs, Mids, and Low. If you have not been doing much of this with your meter. Now would be a great time to start.
2. Throws: Make heavy use of your throws and mix them up. Yes, they can be broken. BUT they will still take something in damage either way. Also, you have crouch throws in your arsenal to help train them. These are your best damage if they are slow on the breaks. but using them to train your opponent once they are forced to block, opens up doors to hitting them with your mids.
3. Close Quarters: K is your friend. Bullrush, Delayed Bullrush, Bullrush BE, 3K_3[ K ] series, 4K_4KK, 6K. All kinds of mid hitting Ks. These kicks are great because A. They hit mid. B. Fairly Fast. C. They are kicks. Meaning that if Maxi wants to play the GI game using his any stance auto gi, they will stuff it.
4. Ranged: Maxi's idea of playing this game with you is having you whiff something and running up to punishing you for it. His 4B is one of his best moves to punish from just beyond his favorite ranges. Play this area smart and try to find a way back in. If the Maxi is dancing about (whiffing moves, to enter stance/stance shifting to bait you in) either A. Stay back and swat him. This option is great if you can ring him out. B. Give him what he wants and Throw down some Bullrush and begin those throw Mix ups.
Break his momentum anyway you can(GI/Poke/throw/etc...), force him to block(choose moves wisely and pressure him), mix throws and mids for the mindgames(once you have him blocking), If he runs away. Watch him. Bait with bG cancels and movement, when he attacks swat at him from a distance and/or charge back in there and get in his face. Make him block you.
my 2 cents...